Lots of great suggestions!

I used the freezer method exclusively, when I was living with one other guy. Our freezer was full of hydration bladders. We’d come home from a trip, pour out the water and toss them in the freezer. One thing I didn't like about this method is the bit of water you didn’t bother to pour out can taste a little "freezer burned". The obvious solution to this is a quick rinse with hot water before you fill it. The nice thing about this is it requires no fussing around trying to keep things clean and dry. I have yet to have a problem with constant freezing/thawing causing the material to get brittle.

Now that I’m married and have a kid, I have to use my freezer for food so I don't really have room to deal with the freezer method. I tend to forget to empty them after trips too. I have had them sit long enough to get a little gross. The interior of the bag gets a little slimy to the touch. But nothing a water/bleach solution and a good couple rinses doesn’t take care of (don't forget to let it flow through the hose and bite valve). It’s a pain, but it’s what I get for being lazy up front!

For any long term storage, I try to get them as dry as possible. I hang mine open side down with something to keep the main bag as open as possible. Most of the major manufacturers sell, as already mentioned, a fancy product to make this part super easy. I have an old Camelbak version that works great. I also use the coat hanger method with great success. Right now, I have one hanging one a hook in my garage with a scrap piece of wood to keep the bag propped open.

The paper towel trick works great to get the bigger pools of water you can’t seem to get out in some bladders. Something I’ve found that works great (not my idea) is to get as much water out as possible. Crumple up a paper towel and shove it in the bladder. Close it back up and blow air into it via the bite valve. Once blown up, shake it around and the towel will collect most of the water.

I never seem to be able to get all the tiny droplets out of the tube. I haven’t had any trouble there though.

Good luck!

m